不同负荷离心运动对大鼠骨骼肌组织结构和血清中酶活性的影响及其意义

目的: 探讨不同负荷运动型大鼠血清肌酸激酶(CK)、乳酸脱氢酶(LDH)与骨骼肌损伤的关系，为科学、准确地判断运动性骨骼肌损伤的研究提供理论依据。方法：70只雄性Wistar大鼠随机分为非运动干预对照组（C）、1次离心运动组(AE)和连续7 d离心运动组(SE)。分别在一次运动和末次训练后即刻、24 h和48 h取腓肠肌和血清，观察腓肠肌的组织结构和血清CK、LDH、丙二醛（MDA）及超氧化物歧化酶（SOD）生物活性的变化。结果：AE组大鼠骨骼肌组织结构在运动后24 h受损严重，SE组在末次运动的即刻骨骼肌组织结构受损严重，光镜下呈现出肌纤维扭曲、皱缩及横纹消失等变化。AE组大鼠血清CK、LDH、MDA活性升高的峰值出现在运动后即刻，与对照组比较差异有统计学意义（P<0.001）；运动后24 h SOD升高显著，与对照组比较差异有统计学意义（P<0.001）；SE组大鼠在末次运动后即刻血清CK、LDH、MDA、SOD明显上升，与对照组比较差异有统计学意义（P<0.001）。结论：一次性离心运动大鼠血清CK、LDH和MAD活性升高的峰值与骨骼肌组织损伤的峰值不同步,骨骼肌组织损伤具有一定的延迟现象。连续7 d离心运动，大鼠血清CK、LDH、MAD和SOD活性升高的峰值与骨骼肌组织损伤的峰值相一致，LDH可作为评价骨骼肌损伤后恢复程度的一个间接指标。

Influence of different eccentric exercise load in tissue structure of skeletal muscle and enzyme activity in rat serum and its significances

Objective To discuss the relationships between the serum creatine kinase(CK),lactate dehydrogenase(LDH) and skeletal muscle injury in rats after different load movement and to provide a theoretical basis for study on muscle injury with scientific and accurate judgement.Methods 70 Wistar male rats were divided into non-exercise group(control group),a bout of eccentric exercise group(AE) and 7 d eccentric movement group(SE).Gastrocnemius were taken immediately,24 h and 7 d after a bout of eccentric exercise or the last exercise,respectively.The changes of tissue structure and serum CK,LDH,malondialdehyde(MAD) and superoxide dismutase(SOD) activities were observed.Results The tissue structure of skeletal muscle of rats in AE group was damaged seriously 24 h after a bout of eccentric exercise;the tissue structure in SE group was also damaged seriously in the immediate time at the last exercise,showing the muscle fiber distortion,shrinkage,disappearance of cross striations and other changes.The activities of serum CK,LDH and MDA reached the peak in the immediate time after exercise in AE group,there were significant differences compared with control group(P<0.001).The activity of serum SOD was increased significantly 24 h after exercise in AE groups compared with control group(P<0.001).The activities of serum CK,LDH,MDA,and SOD in SE group were significantly increased in the immediate time after the last exercise,and the differences between SE group and control group were significant(P<0.001).Conclusion The activities of serum CK,LDH and MAD of rats appears time course changes,and it is not consistent with the skeletal muscle tissue damage,and the changes of skeletal muscle injury has a certain delay phenomenon.The activity peaks of serum CK,LDH,MAD,and SOD 7 d after eccentric exercise are consistent with the skeletal muscle injury.LDH can be the indirect index to evaluate the repair degree of the skeletal muscle injury after eccentric exercise.